$2x-x+7x$

$y\cdot y^7$

$\frac{d^2}{dx^2}\left(y=2\ln\left(x\right)\right)$

$\int\frac{x\:sin\:\left(x^2\right)}{\cos\left(x^2\right)+1}dx$

$\frac{dy}{dx}=y'\left(x\right)=y\left(x\right)+x+x\:y\left(x\right)+1$

$\lim_{x\to-2}\left(\frac{8}{4-x^2}-\frac{1}{2+x}\right)$

$\frac{-6^{19}}{-6^{16}}$